The present invention relates to a sealing device and a wound closure device.
During certain types of medical surgery or treatment an introducer is used to access the vascular system of a patient. The introducer is inserted through the wall of a blood vessel in order to obtain access to the vascular system and may thereafter be used for guiding medical instruments such as catheters, guide wires and the like.
After the completion of the medical procedure there will be an incision or a wound in the wall of the blood vessel corresponding to the size of the introducer. The bleeding from the wound, which is the result of such a surgical operation, may be stopped by applying direct pressure on the wound. However, applying direct pressure on the wound will require assistance of medical personnel and may also restrict the blood flow through the vessel.
U.S. Pat. No. 5,342,393 describes a sealing device for sealing a perforation in the wall of a blood vessel. The device is in the form a two-part rivet, which seals the hole from both the inside and the outside of the vessel. Two rivet portions, an outer rivet portion and an inner rivet portion, are provided which are bayonet or screw threadedly interlocked to clamp the vessel wall. A problem with such a sealing device is that when screwing the outer rivet portion also the inner rivet portion will rotate since there is no holding-up on the inner rivet portion from the inside of the vessel, and thus it is hard to know if the sealing device is properly sealed or not. The latter may have disastrous consequences with blood leaking vessels.
U.S. Pat. No. 5,342,393 also discloses a sealing device, locked together via interlocking ridges. The inner rivet stem has triangular ridges that define horizontal shoulders and the outer rivet may have one or more upside down triangular ridges that define an opposing shoulder for engaging an adjacent shoulder and to thereby allow the outer rivet to be slid over the inner rivet but prevent separating movement. So in this sealing device, both the inner rivet stem and the outer rivet have so-called saw teeth.
The inventors have found that a problem with this sealing device is that the distance between the two occluders (i.e. rivets) may be varied only between fixed positions and thus cannot be exactly adapted to the thickness of the vessel. This in turn can lead to deteriorated tightening of the vessel if the distance exceeds the thickness of the vessel. On the other hand, it can also lead to the vessel being clamped with undue pressure on the vessel, which in turn might result in tissue necrosis or rupture of the arterial wall, when the distance is less than the thickness of the vessel.
U.S. Pat. No. 5,350,399 shows another sealing device for sealing a perforation in the wall of a blood vessel. The sealing device is constructed of a first member in the form of an intra-arterial occluder comprising a guide means in the form of an elongated wire integral with and extending centrally from the intra-arterial occluder and a second member in the form of an extra-arterial occluder. The guide includes a portion extending from the intra-arterial occluder which contains a plurality of saw teeth while the extra-arterial occluder is provided with an opening through which the guide passes. The saw teeth are wider in diameter than the opening in the extra-arterial occluder so that the extra-arterial occluder can be passed over the teeth in a direction towards the intra-arterial occluder.
The above mentioned problem, with the distance between the two occluders being varied only between fixed positions and thus cannot be exactly adapted to the thickness of the vessel, also arises in this sealing device.
A solution to the problem concerning saw teeth would be to provide very fine divided saw teeth, but this would be very unpractical and would give rise to manufacturing problems.
A sealing device commonly is inserted via an elongated introducer extending not perpendicular to the blood vessel, but in an acute angle towards the vessel, to get an insertion direction which is as close to the direction of the vessel as possible. This implies that the surfaces of the sealing device that are to be in contact with the surface of the vessel wall are not parallel to the surface of the vessel in the sealing moment, but in an acute angle to the surface of the vessel.
This reveals another problem in all the above mentioned sealing devices of prior art, if they have a rather stiff inner rivet stem portion extending centrally from the intra-arterial occluder. This problem concerns the difficulty of bringing the two occluders close enough to each other so as to tighten the vessel, because if the occluders cannot be adapted to the vessel wall, the vessel wall has to be deformed to fit towards the occluders which requires an increased sealing force between the occluders.
The angle also causes tensions to the elastic vessel wall since the vessel wall that is in contact with the sealing device becomes parallel to the surface of the occluders which makes the incision of the vessel wall dilated and the tightening more difficult.
The inventors found that these two problems do not arise at all when the sealing device surfaces are parallel to the vessel surface in the sealing moment, but the problem increases the larger the angle becomes.
The inventors found that if the inner rivet stem portion on the other hand is not stiff but flexible, the surface of the inner rivet portion will easy be adjusted to a position, which is parallel to the surface of the vessel. The stem closest to the inner rivet will be perpendicular to the inner rivet surface and the surface of the vessel, but be bent and making an arc, towards the acute angle of the elongated introducer where it thus is perpendicular to the surface of the outer rivet which is to be in contact with the surface of the vessel. The distance between the saw teeth on the stem will then be different on the outside and the inside of said arc, making it problematic to get a good engagement between the saw teeth on the stem and the outer rivet.
Thus there is a need in the art for a sealing device having improved and more secure sealing properties.
The objective problem to be solved by the present invention is to provide a sealing device for closing a wound, which has enhanced tightening properties.
This problem is solved by the invention described herein.
The invention is a device for closing a wound having an elongate member, a first sealing member, and a second sealing member. The second sealing member has an opening such that the second sealing member is threadable onto and along the elongate member. The elongate member includes a distal lock portion having a thickness greater than the opening of the second sealing member such that when the second sealing member is thread onto and along the elongate member, it is infinitely variable lockable along the distal lock portion.
Since the elongated member constitutes or is coated by a suture wire, and has a constant thickness along its lock portion, the thickness being greater than the opening of the second sealing member, the sealing device is infinitely variable lockable along the distal lock portion.
Preferred embodiments of the plug according to the invention are described below.
Thus, it is believed that the present invention provides a novel and easy-to-use sealing and wound closure device for closing a wound with excellent sealing properties.